D-STAR - TH-D74A

Diving into D-STAR – TH-D74A

By Toshen, KEØFHS

(Updated Jul 2018, CC BY-SA)

Programming the TH-D74A for D-STAR

Updated for firmware v1.08; MCP v1.03.

While this section is focused on the Kenwood TH-D74A as well as the Kenwood MCP-D74 Memory Control Program, it contains some information that anyone setting up a radio for use with a D-STAR hotspot might find helpful.

Apologies right up front!

*** This is the most information dense section of the D-STAR article, but I think it's valuable information, so grab a cup of coffee or tea and take a deep breath.…

Hotspot note:

*** If you're going to be using a hotspot for D-STAR, it's really important that you set up your radio properly. For most hotspot devices, DV mode won't work; instead, you must set up RPT1, RPT2, and a zero offset (either +/−0.000). This is known as Duplex mode or D-STAR Repeater (DR) mode.

Even though I'm focused on setting things up for a hotspot, there are a couple aspects of programming the radio that apply to everyone using D-STAR, like MY CALL and TX MESSAGE.

MY CALL. The very first thing everyone using D-STAR needs to do is to enter their callsign in the MY CALL field of their radio. In the TH-D74A, that's done in Menu 610: D-STAR ≫ TX/RX ≫ My Callsign. Enter your call sign in the lefthand field, and a four-digit "memo" in the righthand field, for example, your radio model (I used "D74A") or your name.

TX MESSAGE. In the same TX/RX submenu, you also can enter a brief TX MESSAGE phrase (up to 19 characters) to be transmitted to people, repeaters, and reflectors receiving your call. I entered my name and hometown: Toshen - Lyons, CO.

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Intermission

The TH-D74A has two digital voice modes: Digital Voice (DV) mode for direct simplex calls, and D-STAR Repeater (DR) mode for calls using a D-STAR repeater or hotspot.

Once I got this far, I did set up a couple local (but out-of-range) D-STAR repeaters in the normal way using DR mode, picking them from the local repeater list, and using Destination Select ≫ Direct Input (UR CALL) to set UR CALL to CQCQCQ, for example:

Repeater: KC0DS Mode: DR Frequency: 446.8625 − Via Destination Select ≫ Direct Input (URCALL):

UR CALL: CQCQCQ Via Repeater Select:

RPT1: KC0DS B RPT2: KC0DS G MY CALL: KE0FHS

Then I drove to within range of the repeaters and performed a successful test. That was confirmation I was on the right path.

Note: RPT 1 = the port I'm linking to. RPT 2 = the port I want my transmission routed to. Setting RPT 2 to the repeater's G port doesn't matter, except if someone is linked to the repeater via a hotspot; in that case, they'll only hear you if you've set RPT 2 to port G, which automatically happens when you use Direct Input (UR CALL). I discuss this more in a note on page 3 of this article: Fit the alphabet letters together properly*⩘ *.

For more info about regular D-STAR Use

Since I use a hotspot for nearly all my D-STAR activity, I really don't know much more about programming the radio for regular D-STAR use (in other words, using it for D-STAR when not using a hotspot).

Here are a few resources for learning regular D-STAR use:

Programming TH D74 software for a DVAP using DR mode*⩘ *, 2017, Don Arnold, W6GPS. This is a good video about programming for DR mode.
*Nifty E-Z Guide to D-STAR Operation**⩘ * (2014) by Bernie Lafreniere, N6FN
D-STAR Quick-Start Guide*⩘ * (undated) by Rob Locher, W7GH.
ircDDB Call Sign Routing*⩘ *: Using Call Sign Routing via a Raspberry Pi D-STAR Hotspot, 2017, by Jeff, VE6DV

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2) Set up radio for using a hotspot

The basic method for linking to and using reflectors and repeaters via a hotspot is to:

Link to the reflector or repeater via the hotspot.
Use CQCQCQ to chat.
When finished, unlink from the reflector or repeater.

Since this is a wash, rinse, and repeat type of cycle, it also can be very helpful to set up frequently used repeaters, reflectors, and various D-STAR-related commands in memory channels.

★ Use DR mode!

One thing I said in my foreword is that I'm going back and revising this article as I learn more. This is one area where that's the case. What I had read online initially had led me to believe that I should use and program memories for the hotspots using DV mode (without using the RPT 1 and RPT 2) fields, so I originally used that approach and wrote the rest of this section based on it.

However, when I joined the Kenwood_TH-D74*⩘ * group, I learned something from John Hays, K7VE, of NW Digital Radio*⩘ *, an authoritative voice in this field. In a thread about programming a DVAP*⩘ *, he pointed out that using DV isn't the correct method to use, even though some hotspot device makers support that method in an attempt to make it easier to use their devices. Instead, John says we should be using D-STAR Repeater (DR) mode:

In the D-STAR protocol there is a bit in the header that says, this payload (transmission) is to be repeated.…¹ This bit should always be set to 1 (true) when a transmission is to be repeated (or relayed). DVAPs, DVMegas, > > Hotspots*> ⩘ *> , … all are 'repeating' or 'relaying' D-STAR transmissions to and from RF, and thus when transmitting from your radio to such devices they are 'repeaters' and the bit should be set.

[1] You can see this in the [> > D-STAR System Technical Requirements document*> ⩘ *> (PDF)] para. 2.1.1 (3) Bit 6.

So I changed my own setup to use DR, and revised this section of the article to add instructions for how to set up and use DR mode. While it's a bit more challenging to set up, once it's configured, it's easy to use.

That said, because some hotspot makers have made it possible to use DV mode, I've left the DV mode instructions as well, and you can choose which mode you want to set up and use. I have ***

clearly marked

*** which steps are required for both modes, and which are specific to only one.

Important! If you're using Pi-Star to run a hotspot for D-STAR, it doesn't work to use DV mode. Instead, you must set up your radio using DR mode. You must set up RPT1, RPT2, and a zero offset (either +/−0.000).

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*2a) **

DR & DV mode: ** Hotspot frequency*

To access my hotspots with the TH-D74A, I decided to use the 433.300 UHF frequency, which as far as I can tell is normally unused in my area. Since the transmission between the two devices is very short range, I set the radio's output power to EL (Economic Low: 0.05 W), which is plenty even when I'm in a different room from the hotspot.

Note: For help choosing a frequency, see your country's band plan (U.S. Band Plan*⩘ *) or the helpful info that Ron, VE1AIC, has posted on his blog: Digital Voice frequencies*⩘ *.

Important! Avoid frequencies used for other purposes, especially for satellites, for example, 435.00 - 438.00 (used for satellites internationally), as satellite communication can be disrupted easily by low power transmissions, such as those used for digital voice.

*2b) **

DR mode only: ** Add hotspot to repeater list*

Note: This is a long step. If you're setting up for DV mode, you can skip to the next step: 2c) Create op channels for basic D-STAR actions.

The first thing to do is to add your hotspot to your repeater list. I read about various ways that this can be done, but the only way I could get it to work was by using a method that Ed Woodrick, WA4YIH, the guy behind D-STAR Info*⩘ *, explained in a post in the Kenwood_TH-D74*⩘ * group. Thanks, Ed!

Add a repeater via the MCP-D74A software

The method I ended up using was to first add a hotspot to the Repeater List via the Kenwood MCP-D74 Memory Control Program*⩘ *. Once I added the first one and wrote the data to the transceiver, I was able to add additional ones either via the MCP-D74 app or directly in the radio.

Driver signature enforcement

I use a 64-bit Windows 10 laptop for my amateur radio programming. In early 2018, Microsoft released an update that is much stricter in its handling of third-party driver signature verification. Since then, in order to read from and write to my TH-D74A, I have to use an Advanced Boot Option (option 2 in this How-To Geek article*⩘ *) to temporarily disable driver signature enforcement:

To access advanced boot options: Shift + Restart.
Select the Troubleshoot option.
Select Advanced Options.
Select Startup Settings.
In Startup Settings, click Restart.
After clicking Restart, type 7 to select Disable driver signature enforcement.
The computer will restart with driver signature enforcement disabled until you restart again, and then you can read from and write to the TH-D74A via the MCP-D74 program.

To add a hotspot to the repeater list via the MCP-D74 app:

Save a copy of the radio's data:
Open the Kenwood MCP-D74 Memory Control Program.
Connect the TH-D74A via USB cable to the computer, and then turn the radio on.
Read data from the transceiver.
Save the profile as a backup, and then save a different copy to work in.
Import an updated Repeater List from D-STAR Info:
Open the Repeater List Downloads for DR Mode Radios*⩘ * page.
Enter a location, for example, your city, and click Lookup Location.
Select radio model in the drop-down list.
The TH-D74A can store 1,500 repeaters in its Repeater List memory, but you should leave some repeater slots unused. I chose to leave 20 unused, but 50 - 100 might be better if you travel a lot.
Click Download and save it to your computer as a .tsv file.
In the MCP-D74 program, select Repeater List in the left pane, and then click Import Repeater List from File.

7. Find the tsv file you downloaded and import it.

Add the hotspot to the imported Repeater List. Because you imported a regional Repeater List, there will be spare World Regions, Countries, and Groups.
First, create a new virtual World Region, Country, and Group by clicking Edit Area.

Add the names (I used the last empty field in each list and used the name "Hotspots" for all three), and then click OK.

Scroll to the first empty row at the bottom of the repeater list, and then enter the info for the personal access device, starting with the frequency. For example, here are my entries for the DVMEGA:

Frequency: 433.300
Name: DVMEGA
SubName: DVMEGA DUAL
World Region: 6:Hotspots
Country: 150:Hotspots
Group: 300:Hotspots
Callsign (RPT 1): KE0FHS B

(Note: B = using UHF frequency with the DVMEGA)

Gateway (RPT 2): KE0FHS G
Lockout: Not checked = Off
Shift: Plus

Offset: 0.000.00 (sometimes referred to as "Duplex mode")

Important!

*** You read that right! Plus shift, zero offset, which for some reason isn't the same as no shift.

Optionally, you can add location information by selecting the row the hotspot is on and then clicking Edit Repeater. In the dialog box that opens, you can add the following information that's not available by default in the main list view:

Position Accuracy: Approximate/Exact
Latitude in Degrees Minutes: N/S 00°00.00'
Longitude in Degrees Minutes: E/W 000°00.00'
Time Zone: UTC +/−00:00

Save the profile.
Write the data to the transceiver.

Add a repeater directly in the radio

Once you've added the virtual World Region, Country, and Group, and then have written the data to the transceiver, they'll be available in the radio, so optionally you can add more hotspots to the repeater list right in the radio:

In DR mode, press Menu.
Menu 210 = Memory ≫ Repeater List ≫ View List and press ENT.
Choose a World Region (I chose Hotspots) and press ENT.
Choose a County (Hotspots again) and press ENT.
Choose a Group (Hotspots again) and press ENT.
Press Menu to open the Repeater List Menu.
Choose Add and press ENT.
Next, add the appropriate values to all of the fields.
Finally, press Write to save the entry to the Repeater List.

Hint: You also can edit a repeater that's in the Repeater List, but only if it's not selected as the current operating channel.

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*2c) **

DR & DV mode: ** Create op channels for basic actions*

Create four operating channels in the TH-D74A for the basic D-STAR actions (CQCQCQ, echo test, info, and unlink) to be used with the hotspot, all in DR or DV mode, depending on which you've decided to use.

In VFO FM mode, select the frequency to use, in my case: 433.300.
Press Mode until you're in Digital mode, either DV or DR.
If you need to switch to the other mode:
Press [F] then Digital to open the Digital Function menu.
Navigate to 5. DV/DR Select.
Press A/B = OK to change to the other mode.

DR mode only: *** Select the hotspot via Repeater Select:

Press and hold the Multi-Scroll Down Arrow to open the Repeater Select screen.
Choose Repeater List and press ENT.
Navigate to the DVMEGA and press ENT.

DR & DV mode:

*** Create a CQCQCQ operating channel for talking once a link to a reflector or repeater is established (Note: The last two spaces of the UR CALL field are intentionally left blank):

DR mode only:

Press and hold the Multi-Scroll Up Arrow to open the Destination Select screen.
Use one of two options:

Choose Reflector, press ENT, choose Use Reflector, and then press ENT again. This populates the URCALL field with CQCQCQ.
Choose Direct Input (URCALL), press ENT, type CQCQCQ, and then press ENT again.
Note: Do NOT use the Local CQ option for talking after linking to a reflector or repeater using a hotspot; although this will populate the URCALL field with CQCQCQ like the other options, it also will change the Rpt 2 field, with the consequence that others will not be able to hear you.

Important! Save per the note below: Method to save a channel to memory.

DV mode only:

Press [F] then [Digital] to open the Digital Function Menu, select 1: Destination Select, and then press ENT.
Choose Direct Input (URCALL), and then press ENT.
Type CQCQCQ, and then press ENT again.
Important! Save per the note below: Method to save a channel to memory.

Method to save a channel to memory

This works for both DR and DV modes.

To save the current operating channel to a memory channel:
Press [F] then [2. M.IN.] (M.IN. = Memory In).
Choose a memory channel and press ENT. (You either can save to an empty memory channel or overwrite an existing memory channel.
To name the memory channel:
Press Mode = Edit.
Choose Name and press ENT.
Type a descriptive name and press ENT.
Press Mode = Back.
Press ENT to return to the main frequency screen using the current memory channel's settings.

DR & DV mode:

*** Create the remaining three basic D-STAR action operating channels (Note: blank spaces are shown here with the symbol

⊔ ):

Start with the first four (DR mode) or three (DV mode) steps above.

(Hint: You also can use the shortcut of saving a copy of an existing D-STAR action operating channel, like the CQCQCQ channel you just created, to a new memory channel, after which you can load the main frequency screen with the memory channel's settings and then revise them per the following steps.)

DR mode only:

*** Press and hold the Multi-Scroll Up Arrow to open the Destination Select screen.

DV mode only:

*** Press [F] then [Digital] to open the Digital Function Menu, select 1: Destination Select, and then press ENT.

Choose Direct Input (URCALL) and press ENT.
Create the following operating channels. Set up one at a time, save it to a memory channel, and then set up the next one:

Unlink = Used to unlink from a reflector or repeater (you should always do this when you're finished).

Type 7 blank spaces ( ⊔ ) followed by U: ⊔⊔⊔⊔⊔⊔⊔ U

Echo test (optional) = Used to perform an echo test (when using a hotspot, the echo test is with that device, not the reflector or repeater).

Type 7 blank spaces ( ⊔ ) followed by E: ⊔⊔⊔⊔⊔⊔⊔ E

Info request (optional) = Used to request status information (when using a hotspot, the request for status information is to that device, not the reflector or repeater).

Type 7 blank spaces ( ⊔ ) followed by I: ⊔⊔⊔⊔⊔⊔⊔ I

Note for echo tests and info requests: When linking directly to a repeater (not via a hotspot), the repeater's callsign should be entered followed by E or I in the 8th position. Thanks to Dave, N6XVZ, for pointing this out.

Save per the note above: Method to save a channel to memory.

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*2d) **

DR & DV mode: ** Create op channel for reflector or repeater*

To link to and use a reflector or repeater via a hotspot, begin with the first four steps in the previous procedure (or use the memory channel copy shortcut), and then:

Select the destination repeater or reflector via Destination Select:

DR mode only:

*** Press and hold the Multi-Scroll Up Arrow to open the Destination Select screen.

DV mode only:

*** Press [F] then [Digital] to open the Digital Function Menu, select 1: Destination Select, and then press ENT.

Choose Direct Input (URCALL) and press ENT.
Enter the link command for the reflector or repeater.

For example, XRF223BL = transmit a link request (L) to module B of the XRF223 reflector.

Optionally, for a repeater or reflector you're going to frequently link to and use via the hotspot, save per the note above: Method to save a channel to memory.

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3) Additional radio programming notes

A few more notes related to programming and using a D-STAR radio.

3a) Using the U, E, I, and linking memory channels

To use these channels, you select them and then push PTT for at least one full second ("one, one thousand").

3b) Using CQCQCQ

When using the CQCQCQ channel, you press PTT to talk just as you would with any radio call, but because there can be a slight delay before the transmission is established, you should push and hold PTT, pause at least one full second, and then begin talking. If you don't pause, your first words likely will get cut off.

3c) Reusing the CQCQCQ, U, E, and I memory channels

You can reuse these channels with all of the reflectors and repeaters that you link to via the hotspot. So when you want to add another reflector or repeater into memory, you need to add only the specific link request.

3d) Linking to repeaters with shorter callsigns

If you're linking to a repeater with a callsign shorter than six digits, leave enough blank spaces (

⊔

) between the callsign and the module + link letters to put the L in the eighth space, for example:

KC0DS ⊔

CL = Transmit a link request (L) to the VHF module (C) of the KC0DS D-STAR repeater.

When you enter a 5-digit callsign like this example, put one space ( ⊔

) between the callsign and the "CL" letters. For a 4-digit callsign, put two spaces (

⊔⊔ ).

3e) Organizing the memory channels

Since I'm adding a lot of reflectors and repeaters into my memory channels that I'll be linking to via my hotspot, it became important to organize my memory channels well.

I have set them up in blocks of ten. The first channel in a block is a CQCQCQ talk channel, and the second is an unlink channel. Then the remaining eight channels in the block are reflector or repeater linking channels. That way, I can:

Select a linking channel.
PTT to link.
Quickly select the nearest CQCQCQ channel and chat.
At the end of the call, select the nearest unlink channel and PTT to terminate the link.

Since I don't often use the optional echo test and info request commands, I added them only to the first block of ten.

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